CN114293075B - Aluminum-zinc-silicon-lead alloy for thin-wall bearing bush and preparation method of alloy sheet - Google Patents
Aluminum-zinc-silicon-lead alloy for thin-wall bearing bush and preparation method of alloy sheet Download PDFInfo
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Abstract
An aluminum-zinc-silicon-lead alloy for a thin-wall bearing bush comprises the following chemical components in percentage by weight: zn:4.2 to 5.3%, si:1.2 to 1.9%, cu:0.9 to 1.3%, mg:0.01 to 0.65%, pb:0.60 to 1.3%, ti:0.01 to 0.3%, fe: the method for preparing the alloy sheet by the aluminum-zinc-silicon-lead alloy comprises the steps of carrying out homogenization annealing treatment on an alloy ingot blank, removing surface defects by machining, and then carrying out hot rolling and cold rolling, wherein the content of each of the other impurity elements is less than or equal to 0.05%, the total content of the impurity elements is less than or equal to 0.15%, and the balance is Al. The invention improves the performance of the aluminum-zinc-silicon-lead alloy, can prepare the cold-rolled alloy sheet with the hardness of more than or equal to HV80 by means of reasonably designing alloy components, optimizing a heat treatment process, adjusting a rolling process and the like, effectively avoids the defects of opening, edge cracking, bulging and the like which are easy to appear in the sheet rolling process, ensures the internal quality of the alloy sheet, and can meet the material selection requirement of the thin-wall bearing bush on the alloy material in a domestic manner.
Description
Technical Field
The invention relates to the field of thin-wall bearing bush alloy materials, in particular to an aluminum-zinc-silicon-lead alloy for a thin-wall bearing bush and a preparation method of an alloy thin plate.
Background
The acting force applied by the bearing bush bearing journal is called as a fuse of the engine, and when the conditions of overlarge load, overhigh temperature, impurities in lubricating oil, abnormal viscosity and the like occur, the bearing bush can burn, so that the engine is protected from being seriously damaged. Plain bearing materials are materials used to produce parts such as bearing shells, shaft sleeves, etc., which are friction elements that engage directly with a shaft or shaft journal. The sliding bearing material must have good friction reduction, wear resistance, embeddability, compliance, corrosion resistance and sufficient bearing capacity to reduce frictional wear and prolong the service life of the bearing.
The existing thin-wall bearing bush is generally composed of three layers: the steel backing + alloy layer + surface bearing layer, the alloy layer usually adopts aluminum alloy, copper alloy and the like, and the aluminum-based bearing alloy has the advantages of light weight, high specific strength, high fatigue resistance, good surface performance and corrosion resistance, rich resources and low price, and becomes the leading material of the thin-walled bearing bush of the high-speed high-load diesel engine. At present, the performance of the existing thin-wall bearing bush alloy material in China is insufficient, the preparation process is not mature enough, and the aluminum alloy bearing bush for the high-speed diesel engine is caused to depend on import seriously, so that the realization of domestic autonomous guarantee of the bearing bush material has very important significance.
Disclosure of Invention
The invention aims to provide an aluminum-zinc-silicon-lead alloy for a thin-wall bearing bush and a preparation method of an alloy sheet, which can improve the performance of the aluminum-zinc-silicon-lead alloy and ensure the quality of the alloy sheet.
The technical scheme adopted by the invention for solving the technical problems is as follows: an aluminum-zinc-silicon-lead alloy for a thin-wall bearing bush comprises the following chemical components in percentage by weight: zn:4.2 to 5.3%, si:1.2 to 1.9%, cu:0.9 to 1.3%, mg:0.01 to 0.65%, pb:0.60 to 1.3%, ti:0.01 to 0.3%, fe: less than or equal to 0.05 percent, less than or equal to 0.05 percent of single content of other impurity elements, less than or equal to 0.15 percent of total content of impurity elements and the balance of Al.
Preferably, the alloy comprises the following chemical components in percentage by weight: zn:5.20%, si:1.78%, cu:1.20%, mg:0.617%, pb:0.62%, ti:0.12%, fe:0.020%.
Preferably, the alloy comprises the following chemical components in percentage by weight: zn:4.95%, si:1.80%, cu:1.21%, mg:0.618%, pb:1.06%, ti:0.13%, fe:0.024 percent.
Preferably, the alloy comprises the following chemical components in percentage by weight: zn:5.17%, si:1.77%, cu:1.24%, mg:0.594%, pb:1.20%, ti:0.128%, fe:0.022 percent.
Preferably, the alloy comprises the following chemical components in percentage by weight: zn:4.91%, si:1.60%, cu:1.09%, mg:0.53%, pb:1.19%, ti:0.12%, fe:0.022 percent.
According to the method for preparing the alloy sheet by the aluminum-zinc-silicon-lead alloy, the thickness of the alloy sheet is 1.5-2.5 mm, the hardness is more than or equal to HV80, and the method comprises the following steps:
step one, weighing an Al99.99 aluminum ingot, a Zn99.95 zinc ingot, a Mg99.95 magnesium ingot, a Pb99.99 lead ingot, an AlSi20 intermediate alloy, an AlCu50 intermediate alloy and an AlTi5 intermediate alloy as raw materials according to the chemical components of the alloy, and preparing into an aluminum-zinc-silicon-lead alloy ingot blank;
step two, carrying out homogenization annealing treatment on the aluminum-zinc-silicon-lead alloy ingot blank, wherein the annealing process comprises heating to 490 ℃, preserving heat for 2 hours, then heating to 510 ℃, and preserving heat for 6 hours;
step three, machining to remove 2-5 mm of the surface layer of the aluminum-zinc-silicon-lead alloy ingot blank so as to remove surface layer defects;
step four, heating the aluminum-zinc-silicon-lead alloy ingot blank to 300-350 ℃, preserving heat for 1-2 h, and then carrying out hot rolling, wherein the deformation of each pass is 10% -15%, so as to obtain an aluminum-zinc-silicon-lead alloy thick plate with the thickness of 6-7 mm;
and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 300-350 ℃, preserving heat for 6-10 h, cooling to room temperature, and then performing cold rolling, wherein the deformation of each pass is 10-15%, so as to obtain the aluminum-zinc-silicon-lead alloy thin plate with the thickness of 1.5-2.5 mm.
Preferably, in the fourth step, the ingot blank of the aluminum-zinc-silicon-lead alloy is heated to 300 ℃, the temperature is kept for 1h, and the deformation of each hot rolling pass is 15 percent; and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 300 ℃, preserving heat for 8 hours, cooling to room temperature, and then performing cold rolling, wherein the deformation of each cold rolling pass is 13%.
Preferably, in the fourth step, the ingot blank of the aluminum-zinc-silicon-lead alloy is heated to 350 ℃, the temperature is kept for 1h, and the deformation of each hot rolling pass is 15 percent; and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 350 ℃, preserving heat for 8 hours, cooling to room temperature, and then performing cold rolling, wherein the deformation of each cold rolling pass is 13%.
Preferably, in the fourth step, the ingot blank of the aluminum-zinc-silicon-lead alloy is heated to 300 ℃, the temperature is kept for 1h, and the deformation of each hot rolling pass is 15 percent; and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 350 ℃, preserving heat for 8 hours, cooling to room temperature, and then performing cold rolling, wherein the deformation of each cold rolling pass is 10%.
Preferably, in the fourth step, the ingot blank of the aluminum-zinc-silicon-lead alloy is heated to 300 ℃, the temperature is kept for 1h, and the deformation of each hot rolling pass is 10 percent; and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 350 ℃, preserving heat for 8 hours, cooling to room temperature, and then performing cold rolling, wherein the deformation of each cold rolling pass is 15%.
According to the technical scheme, the invention has the beneficial effects that:
the aluminum-zinc-silicon-lead alloy reasonably limits the contents of Zn, si, cu, mg, pb, ti and Fe, improves the performance of the aluminum-zinc-silicon-lead alloy, can meet the performance requirement of a thin-wall bearing bush on an aluminum alloy material, can prepare a cold-rolled alloy sheet with the hardness of more than or equal to HV80 by means of reasonably designing alloy components, optimizing a heat treatment process, adjusting a rolling process and the like, effectively avoids the defects of opening, edge cracking, bulging and the like easily occurring in the sheet rolling process, ensures the internal quality of the alloy sheet, and can meet the material selection requirement of the thin-wall bearing bush on the aluminum alloy material in localization.
Detailed Description
An aluminum-zinc-silicon-lead alloy for a thin-wall bearing bush comprises the following chemical components in percentage by weight: zn:4.2 to 5.3%, si:1.2 to 1.9%, cu:0.9 to 1.3%, mg:0.01 to 0.65%, pb:0.60 to 1.3%, ti:0.01 to 0.3%, fe: less than or equal to 0.05 percent, less than or equal to 0.05 percent of single content of other impurity elements, less than or equal to 0.15 percent of total content of impurity elements and the balance of Al.
According to the method for preparing the alloy sheet by the aluminum-zinc-silicon-lead alloy, the prepared alloy sheet has the thickness of 1.5-2.5 mm and the hardness of more than or equal to HV80, and the method comprises the following steps:
step one, weighing an Al99.99 aluminum ingot, a Zn99.95 zinc ingot, a Mg99.95 magnesium ingot, a Pb99.99 lead ingot, an AlSi20 intermediate alloy, an AlCu50 intermediate alloy and an AlTi5 intermediate alloy as raw materials according to the chemical components of the alloy, and preparing into an aluminum-zinc-silicon-lead alloy ingot blank;
step two, carrying out homogenization annealing treatment on the aluminum-zinc-silicon-lead alloy ingot blank, wherein the annealing process comprises heating to 490 ℃, preserving heat for 2 hours, then heating to 510 ℃, and preserving heat for 6 hours;
step three, machining to remove 2-5 mm of the surface layer of the aluminum-zinc-silicon-lead alloy ingot blank so as to remove surface layer defects;
step four, heating the ingot blank of the aluminum-zinc-silicon-lead alloy to 300-350 ℃, preserving the heat for 1-2 hours, and then carrying out hot rolling, wherein the deformation of each pass is 10-15%, so as to obtain an aluminum-zinc-silicon-lead alloy thick plate with the thickness of 6-7 mm;
and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 300-350 ℃, preserving heat for 6-10 h, cooling to room temperature, and then performing cold rolling, wherein the deformation of each pass is 10-15%, so as to obtain the aluminum-zinc-silicon-lead alloy thin plate with the thickness of 1.5-2.5 mm.
Example 1:
(1) The aluminum-zinc-silicon-lead alloy for the thin-wall bearing bush provided by the embodiment comprises the following components in percentage by mass: zn:5.20%, si:1.78%, cu:1.20%, mg:0.617%, pb:0.62%, ti:0.12%, fe:0.020%.
(2) After carrying out homogenization heat treatment on the aluminum alloy ingot blank at 490 ℃ multiplied by 2h +510 ℃ multiplied by 6h, milling the surface layer for 3mm, heating the ingot blank to 300 ℃, preserving the heat for 1h, carrying out hot rolling, wherein the deformation of hot rolling passes is 15%, and the thickness of the plate after hot rolling is 7mm. And (3) carrying out heat treatment on the hot-rolled plate at 300 ℃ for 8h, cooling to room temperature, and carrying out cold rolling, wherein the deformation of each cold rolling pass is 13%, the thickness of the cold-rolled plate is 2.5mm, and the hardness of the cold-rolled plate is HV80.7.
Example 2:
(1) The aluminum-zinc-silicon-lead alloy for the thin-wall bearing bush provided by the embodiment comprises the following components in percentage by mass: zn:4.95%, si:1.80%, cu:1.21%, mg:0.618%, pb:1.06%, ti:0.13%, fe:0.024 percent.
(2) After carrying out homogenization heat treatment on the aluminum alloy ingot blank at 490 ℃ multiplied by 2h +510 ℃ multiplied by 6h, milling the surface layer for 2mm, heating the ingot blank to 350 ℃, preserving the heat for 1h, carrying out hot rolling, wherein the deformation of hot rolling passes is 15%, and the thickness of the plate after hot rolling is 7mm. And (3) carrying out heat treatment at 350 ℃ for 8h on the hot-rolled plate, cooling to room temperature, and carrying out cold rolling, wherein the deformation of each cold rolling pass is 15%, the thickness of the cold-rolled plate is 2.0mm, and the hardness of the cold-rolled plate is HV81.9.
Example 3:
(1) The aluminum-zinc-silicon-lead alloy for the thin-wall bearing bush provided by the embodiment comprises the following components in percentage by mass: zn:5.17%, si:1.77%, cu:1.24%, mg:0.594%, pb:1.20%, ti:0.128%, fe:0.022 percent.
(2) After carrying out homogenization heat treatment on the aluminum alloy ingot blank at 490 ℃ multiplied by 2h +510 ℃ multiplied by 6h, milling the surface layer for 5mm, heating the ingot blank to 300 ℃, preserving the heat for 1h, carrying out hot rolling, wherein the deformation of hot rolling passes is 15%, and the thickness of the plate after hot rolling is 7mm. And (3) carrying out heat treatment at 350 ℃ for 8h on the hot-rolled plate, cooling to room temperature, and carrying out cold rolling, wherein the deformation of each cold rolling pass is 10%, the thickness of the cold-rolled plate is 1.8mm, and the hardness of the cold-rolled plate is HV84.5.
Example 4:
(1) The aluminum-zinc-silicon-lead alloy for the thin-wall bearing bush provided by the embodiment comprises the following components in percentage by mass: zn:4.91%, si:1.60%, cu:1.09%, mg:0.53%, pb:1.19%, ti:0.12%, fe:0.022 percent.
(2) After carrying out homogenization heat treatment on the aluminum alloy ingot blank at 490 ℃ for 2h +510 ℃ for 6h, milling the surface layer for 3mm, heating the ingot blank to 300 ℃, preserving the heat for 1h, carrying out hot rolling, wherein the deformation of each pass of the hot rolling is 10%, and the thickness of the plate after the hot rolling is 6mm. And (3) carrying out heat treatment on the hot-rolled plate at 350 ℃ for 8h, cooling to room temperature, and carrying out cold rolling, wherein the deformation of each cold rolling pass is 15%, the thickness of the cold-rolled plate is 1.6mm, and the hardness of the cold-rolled plate is HV82.3.
Claims (10)
1. An aluminum-zinc-silicon-lead alloy for a thin-wall bearing bush is characterized in that: the alloy comprises the following chemical components in percentage by weight: zn:4.2 to 5.3%, si:1.2 to 1.9%, cu:0.9 to 1.3%, mg:0.01 to 0.65%, pb:0.60 to 1.3%, ti:0.01 to 0.3%, fe: less than or equal to 0.05 percent, less than or equal to 0.05 percent of the single content of other impurity elements, less than or equal to 0.15 percent of the total content of the impurity elements and the balance of Al; the preparation method of the alloy at least comprises the following steps:
step one, weighing an Al99.99 aluminum ingot, a Zn99.95 zinc ingot, a Mg99.95 magnesium ingot, a Pb99.99 lead ingot, an AlSi20 intermediate alloy, an AlCu50 intermediate alloy and an AlTi5 intermediate alloy as raw materials according to the chemical components of the alloy, and preparing into an aluminum-zinc-silicon-lead alloy ingot blank;
and step two, carrying out homogenization annealing treatment on the aluminum-zinc-silicon-lead alloy ingot blank, wherein the annealing process comprises heating to 490 ℃, preserving heat for 2 hours, then heating to 510 ℃, and preserving heat for 6 hours.
2. An Al-Zn-Si-Pb alloy for thin-walled bearing shells as claimed in claim 1, wherein: the alloy comprises the following chemical components in percentage by weight: zn:5.20%, si:1.78%, cu:1.20%, mg:0.617%, pb:0.62%, ti:0.12%, fe:0.020%.
3. An Al-Zn-Si-Pb alloy for thin-walled bearing shells as claimed in claim 1, wherein: the alloy comprises the following chemical components in percentage by weight: zn:4.95%, si:1.80%, cu:1.21%, mg:0.618%, pb:1.06%, ti:0.13%, fe:0.024 percent.
4. An Al-Zn-Si-Pb alloy for thin-walled bearing shells as claimed in claim 1, wherein: the alloy comprises the following chemical components in percentage by weight: zn:5.17%, si:1.77%, cu:1.24%, mg:0.594%, pb:1.20%, ti:0.128%, fe:0.022 percent.
5. The Al-Zn-Si-Pb alloy for a thin-walled bearing shell as claimed in claim 1, wherein: the alloy comprises the following chemical components in percentage by weight: zn:4.91%, si:1.60%, cu:1.09%, mg:0.53%, pb:1.19%, ti:0.12%, fe:0.022 percent.
6. The method for preparing the alloy sheet from the aluminum-zinc-silicon-lead alloy according to claim 1, wherein the thickness of the alloy sheet is 1.5-2.5 mm, and the hardness is not less than HV80, and the method is characterized by further comprising the following steps:
step three, removing 2-5 mm of the surface layer of the aluminum-zinc-silicon-lead alloy ingot blank by machining so as to remove surface layer defects;
step four, heating the ingot blank of the aluminum-zinc-silicon-lead alloy to 300-350 ℃, preserving the heat for 1-2 hours, and then carrying out hot rolling, wherein the deformation of each pass is 10-15%, so as to obtain an aluminum-zinc-silicon-lead alloy thick plate with the thickness of 6-7 mm;
and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 300-350 ℃, preserving heat for 6-10 h, cooling to room temperature, and then performing cold rolling, wherein the deformation of each pass is 10-15%, so as to obtain the aluminum-zinc-silicon-lead alloy thin plate with the thickness of 1.5-2.5 mm.
7. The method of manufacturing an alloy sheet according to claim 6, wherein: in the fourth step, the ingot blank of the aluminum-zinc-silicon-lead alloy is heated to 300 ℃, the temperature is kept for 1h, and the deformation of each pass of hot rolling is 15 percent; and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 300 ℃, preserving heat for 8 hours, cooling to room temperature, and then performing cold rolling, wherein the deformation of each cold rolling pass is 13%.
8. The method of manufacturing an alloy sheet according to claim 6, wherein: in the fourth step, the ingot blank of the aluminum-zinc-silicon-lead alloy is heated to 350 ℃, the temperature is kept for 1h, and the deformation of each pass of hot rolling is 15 percent; and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 350 ℃, preserving heat for 8 hours, cooling to room temperature, and then performing cold rolling, wherein the deformation of each cold rolling pass is 13%.
9. The method of manufacturing an alloy sheet according to claim 6, wherein: in the fourth step, the ingot blank of the aluminum-zinc-silicon-lead alloy is heated to 300 ℃, the temperature is kept for 1h, and the deformation of each pass of hot rolling is 15 percent; and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 350 ℃, preserving heat for 8 hours, cooling to room temperature, and then performing cold rolling, wherein the deformation of each cold rolling pass is 10%.
10. The method of manufacturing an alloy sheet according to claim 6, wherein: in the fourth step, the ingot blank of the aluminum-zinc-silicon-lead alloy is heated to 300 ℃, the temperature is kept for 1h, and the deformation of each pass of hot rolling is 10 percent; and fifthly, heating the aluminum-zinc-silicon-lead alloy thick plate to 350 ℃, preserving heat for 8 hours, cooling to room temperature, and then performing cold rolling, wherein the deformation of each cold rolling pass is 15%.
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| CN1817634B (en) * | 2006-03-16 | 2012-03-14 | 上海云瀛复合材料有限公司 | Double-layer aluminium-base composite materials, its production and use thereof |
| CN102936676A (en) * | 2011-08-15 | 2013-02-20 | 上海核威实业有限公司 | Aluminum zinc silicon material, aluminum zinc silicon-steel metal bearing material and manufacturing processes thereof |
| CN103667823B (en) * | 2013-08-19 | 2016-07-06 | 上海云瀛复合材料有限公司 | A kind of high intensity aluminum zinc magnesium alloy material and its preparation method and application |
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